Excavator



April 15, 1930. G. H. GREIMAN I EXCAVATOR Filed Feb. 11, 1928 2 Sheets-Sheet l fijwnfaz 6601ffl6 fif 61 61717017 539 Z18 471 05111 15 Wow/Z April 1930. G. H. GREIMAN 1,754,551

EXGAVATOR Filed Feb 11. 1928 2 Sheets-Sheet 2 Patented Apr. 15, 1930 series.

GEORGE E. GREIMAN, OF GARNER, IOWA.

EXCAVATOR Application filed February 11, 1928. Serial No. 253,691.

My present invention relates to excavators and, more particularly, to the type commonly called trenchers, that are especially adapted for use in digging ditches or trenches in which are to be laid sewer, water, gas, drain or other pipes.

To the above end, generally stated, the invention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

The invention is directed primarily to the transverse conveyor of the trencher onto which dirt is discharged from the buckets of the elevator and carried by said conveyor to one side of the trencher.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a side elevation of a trencher having the invention embodied therein;

Fig. 2 is a plan view of the transverse conveyor and a portion of the trencher, on an enlarged scale; and i Fig. 3 is a rear end elevation with some parts removed and also illustrating, by means of broken lines, the transverse conveyor folded.

The invention, as shown, is embodied in a self-propelled trencher and, of the parts thereof, except its transverse conveyor, it is only necessary to note the truck frame 4, supported by front wheels 5 and by rear wheels, not shown, over which run tread chains 6. For the purposes of this case, it is not thr-ought necessary to consider the mechanism for driving the rear wheels for operating the traction chains 6 from an engine 7 on the truck frame 4. Mounted on the truck frame 4 is a main frame 8 which includes front and rear pairs of upright posts 9 between which thetransverse conveyor works.

The boom 10, at its inner end, is pivoted on a driven shaft 11 journaledon a trussed rearwardly projecting boom-supporting frame 12 that is rigidly secured to the truck frame 4 and main frame 8. Sprocket chains 13 run over sprocket wheels 14 on the shaft 11 and similar wheels 15 ournaled on the boom 10 at the free end thereof. Tooth-equipped back ets 16 are carried by the sprocket chains 13 and are of the type that pick up their loads at their front edges and discharge the same at their rear edges. This discharge of the loads takes place as the buckets make the upward turning movement around the shaft 11 and sprocket wheels 14, and the transverse conveyor is arranged to receive the dirt discharged from said buckets. The shaft 11 is driven from the engine 7 at the proper speed through any suitable transmission rnechanism indicated as an entirety by the numeral 1a.

For raising and lowering the boom 10, a cable 18 is provided and arranged to run over a guide sheave 19 on said boom and a guide sheave 20 on the frame 12, and is attached to a windlass drum indicated as an entirety by the numeral 21 and operated, at will, from the transmission mechanism 17.

The transverse conveyor heretofore referred to, and which is the primary subjectmatter of the present invention, includes a segmental frame 22 that extends between the front and rear pairs of posts 9 for swinging movement transversely of the trencher. This frame 22, as shown, comprises four straight sections arranged on the arc of a circle and connected by hinges 23. These hinges 23 areso arranged that, when the conveyor is projected on either side of the trencher, the two outermost sections thereof may be folded as indicated by broken lines in Fig. 3, so that said conveyor does not project outward of the trencher when not in use. The hinges 23 connecting the end sections of the frame 22 are on the under side thereof, and the abutting ends of the connected sections prevent folding movement thereof, while the hinges 23, connecting the two intermediate sections, are on top thereof, and a suitable lock, not shown, will be provided to hold said sections from moving on the hinge when in' operative positions.

An endless conveyor belt 2 is arranged to run over rollers 25 journaled on the ends of the frame 22, and the upper section of said belt is supported ona plurality of relatively small rollers 26 journaled on the frame 22, and guide rollers for the under section of the belt 24 are journaled on the frame 22. The belt 24 is driven by a sprocket chain 28 arranged to run over sprocket wheels 29 on the rollers 25, a driven sprocket wheel 30 and under an idle sprocket wheel 31 on the main frame 8. The shaft 32 on which the sprocket wheel 30 is keyed, is driven from the transmission mechanism 17 by any suitable connections and, for the purposes of this case, it is not thought necessary to illustrate the same.

The transverse conveyor is suspended by two pairs of toggle joints for swinging movement transversely of the trencher in substait tially the arc of a circle, to be projected on either side of said trencher. These two pairs of toggle joints are reversely extended transversely over the top of the main frame 8 to opposite sides of the trencher.

The outer bars of the toggle joints are indicated by the numeral 33 and the inner bars thereof are indicated by the numeral 34. Said inner bars 34 of the two pairs of toggle joints are in crossed relation and their outer ends are pivoted to anchor blocks 35 on the main frame 8 at the top thereof, and the joints between the bars 33 and 34 are outward of said main frame. The outer ends of the bars 33 are pivoted at 36 to the ends of the frame 22 outward of the longitudinal ec ges of the belt 24.

The bars 33 have intermediate fulcrunied rollers 37 journaled thereto and so arranged that the inner end portions of the arms 33 are relatively short and the outer end portions thereof are relatively long. These fulcrum rollers 37 are arranged to run in reverse directions on cam-acting fulcrum bases 38 rigidly secured to the outer end portions of horizontal rails 39 on the main frame 8. Said fulcrum bases 38, as shown, are in the form of channel-shaped tracks that hold the fulcrum rollers 37 for straight-line travelling movements.

The two pairs of toggle joints 3334 are arranged to reversely operate, that is, when one pair thereof is straightening, the other pair thereof is buckling and the fulcrum bases 38 are so shaped as to cause the toggle joints to hold the conveyor in substantially the arc of a circle during its swinging movement. The pair of toggle joints supporting the inner or lower end of the conveyor are buckled, and the outer bars 33 thereof are in vertical positions, while the pair of toggle joints supporting the outer or raised end of said conveyor are straight and the outer bars 33 thereof extend transversely oblique to the main frame 8.

It is important to note that the vertical bars 33, as shown in Fig. 3, are under direct tension and support the lower end portion of the conveyor closely to where the loads are dumped thereon from the buckets 16 and absorb substantially all of the shock while the oblique bars 33 supporting the raised end of the conveyor takes very little of the shock.

The fulcrum bases 38 are so shaped that in projecting the conveyor to the opposite side of the trencher from that in which it is positioned causes very little lifting movement of the lower end of the conveyor during the initial swinging movement of said conveyor and. the initial straightening movement of the respective toggle joint is relatively slight, but during the balance of this projecting movement of the conveyor the lower end thereof is raised relatively fast as the respective fulcrum rollers 37 move downward on the fulcrum bases 38 on which they are mounted. Of course, the action of the straight toggle joints as they are being buckled by the travel of their fulcrum rollers 37 on the fulcrum bases 38 on which they are mounted impart a substantially similar movement to the raised end of the conveyor as it is lowered so that said conveyor moves in substantially the arc of a circle during its projecting movement from one side of the main frame 8 to the other. The action of the toggle joints on the conveyor during its swinging movement is such that said conveyor within the main frame 8 is always at substantially the same elevation so as to clear the various adjacent parts of the trencher.

\Vhen the conveyor is positioned with a portion thereof folded as shown by broken lines in Fig. 3, the folded sections thereof are held in position by a cable 40 arranged to be wound on a windlass drum indicated as an entirety by the numeral 41 and having its outer end attached by a hook or other suitable means to an eye 42 on one of the folded sections of the frame 22. It is important to note that the fulcrum rollers 37 loosely rest on the fulcrum bases 38 so that the toggle joints may be lifted, as one thereof is indicated by broken lines in Fig. 3, when the conveyor is folded.

To move the conveyor from one side of the trencher to the other and hold the same where set there is provided a pair of laterally spaced cables 43 which extend longitudinally of the conveyor and have their ends attached to the ends of said conveyor. The intermediate portions of the cables 43 are secured to and arranged to be reversely wound on win dlass drums indicated as an entirety by the numeral 44. During the projecting movement of the conveyor the sections of the cables 43 attached to the end of the frame 22 moving away from the windlass drums 44 are unwound from said drums and the other end portions of the cables 43 are wound on said windlass drums to swing the conveyor transversely of the main frame 8. The shaft 45 on which the windlass drums 44 are secured is journaled on the main frame 8 and is driven, at will from a shaft 46 journaled in said frame and having a worm 47 which meshes with a worm gear 48 on the shaft L5. A sprocket wheel 49 on the shaft 4.6 is driven by any suitable connections, not shown, from the transmission mechanism 17.

What I claim is 1. In an excavator, the combination with a frame, of a transverse conveyor, and compensating connections suspending the conveyor at each end from the frame for swinging movement on the line of a curve transversely of the frame and permitting the conveyor to be projected on either side of the frame and to cause the same to raise on the side of the frame on which it is being pror jected and in which the connection on the raising end of the conveyor automatically and progressively lengthens during the outward movement of the conveyor to progres sively flatten the curve on which the conveyor is being moved.

2. In an excavator, the combination with a frame, of a transverse conveyor, and two toggle joints suspending the conveyor from the frame for swinging movement transversely thereof and permitting said conveyor to be projected on either side of the frame, one of the bars of each toggle joint being intermediately fulcrumed on the frame for shifting movement transversely thereof, one of said toggle joints being arranged to straighten and the other to buckle during the project-ing movement of the conveyor on either side of the frame.

3. The structure defined in claim 2 in which the straightening and buckling movements of the toggle joints raises one end of the conveyor and lowers the other.

4. In an excavator, the combination with a frame having cam-acting fulcrum bases, of a transverse conveyor, and two reversely extended toggle joints suspending the conveyor from the frame for swinging movement transversely thereof and permitting the conveyor to be projected on either side of the frame, the inner bars of the toggle joints being pivotally anchored in respect to the frame and the outer bars thereof being pivoted one to each end of the conveyor, said outer bars having intermediate fulcrums mounted on the fulcrum bases for shifting movements, said fulcrum bases being arranged when the conveyor is projected on either side of the frame to buckle one of the toggle levers and straighten the other thereof to raise one end of the conveyor and lower the other.

5. The structure defined in claim l in which the inner bars are in crossed relation with their pivoted ends anchored to opposite sides of the frame.

6. In an excavator, the combination with a frame having cam-acting fulcrum bases, of a transverse conveyor, and two reversely extended toggle joints suspending the conveyor from the frame for swinging movement transversely thereof and permitting theconveyor to be projected on either side of the frame, the inner bars of the toggle joints being crossed and pivoted to the frame on opposite sides thereof and the outer bars thereof being pivotally attached one to each end of the conveyor and having intermediate fulcrum rollers arranged to travel in reverse directions on the fulcrum bases during the projecting movement of the conveyor on either side of the frame and straighten one of the toggle joints to raise the respective end of the conveyor and buckle the other of said joints to lower the respective end of the conveyor, said conveyor being held by the toggle joints at substantially a constant elevation within the frame during their straightening and buckling movements and when projected on either side of the frame.

7. The structure defined in claim 2 in which the conveyor comprises a substantially segmental frame and an endless travelling belt mounted on the segmental frame.

8. The structure defined in claim 2 in which the conveyor comprises a folding sectional substantially segn'iental frame, and an endless travelling belt mounted on the segmental frame.

The structure defined in claim 2 in which the conveyor comprises a folding sectional :-.zubstantially segmental frame, and an endless travelling belt mounted on the segmental frame, and in which the fulcrum of either one of the toggle oints is free to lift to permit the projected end portions of the conveyor to be folded.

In testimony whereof I affiX my signature GEORGE H. GREIMAN. 

